Feb 16, 2024 - Research

The Genetics of Loneliness and its Impact on Health

Editor’s Note: We first published this post on the heels of our collaboration with the University of California San Diego researchers. It offers some stark reminders that loneliness has a cost not just on our mental health but our physical health as well. A new report by the Centers for Disease Control reminded us of the growing number of people alone in the United States. It also reminded us of how serious a problem loneliness is for our health, as detrimental to our health as smoking. In light of that report and others looking at the rise in mental health issues among adults, we wanted to resurface this post from 2020.

Humans are social animals. We thrive through contact with other people, and the importance of that connection can be seen by what happens in its absence.

Loneliness has an impact on health.

Several studies have shown the damaging impact loneliness has on human health. The adverse health effects of loneliness rival that of smoking and obesity, according to recent studies done by scientists at UC San Diego.

Loneliness, A Growing Problem

Growing isolation and loneliness, particularly among the elderly, have prompted public health responses. Two years ago, the United Kingdom created the first national strategy to deal with the health consequences of isolation. The National Academies of Sciences have begun to study the problem in the United States. 

But beyond trying to combat social isolation, scientists are also researching for possible genetic predispositions toward loneliness. They also look at where those associations might overlap with risks for specific health outcomes. 

Genetics Also Plays a Role

Two recently completed studies offer compelling evidence of a genetic predisposition toward loneliness. Both studies, which included data from 23andMe and the UK Biobank, found shared genetic associations between loneliness and other conditions like cardiovascular disease, as well as psychiatric and metabolic disorders.

­­One study, led by researchers at the University of California at San Diego, found a clear association between loneliness and coronary artery disease, particularly among women. The study, published in Human Molecular Genetics, used data from more than half a million individuals. The researchers found 19 variants associated with a predisposition toward loneliness. Those variants were also associated with cardiovascular disease, as well as some psychiatric and metabolic disorders. Associations between major depressive disorder, loneliness, and heart disease have been described in previous studies.  However, this study found that the associations are partly explained by genetics.

In another Vanderbilt University Medical Center study, researchers used electronic medical records and data from 23andMe, the UK Biobank, and others. That study looked at the connections between loneliness, major depressive disorder, and coronary artery disease. That study found that individuals with genetic risk for loneliness and major depressive disorder were more likely to have clinical diagnoses for coronary artery disease. This association was stronger in women than men, and the effect was specific to loneliness.

The studies come amid increased attention to the genuine public health consequences of loneliness, particularly among older people. The researchers suggest that understanding conditions associated with loneliness could help develop ways to address the issue.

Find Out More

23andMe does not have a report on loneliness, but 23andMe+ members can learn about conditions associated with loneliness, such as their genetic predisposition toward Depression and Anxiety.

Current 23andMe Health + Ancestry Service customers on the current genotyping chip can receive this report and 35+ other reports by joining 23andMe+ from within their accounts.

Not a 23andMe+ customer yet? Learn more about what 23andMe has to offer here.

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